5,292 research outputs found

    Diophantine Undecidability of Holomorphy Rings of Function Fields of Characteristic 0

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    Let KK be a one-variable function field over a field of constants of characteristic 0. Let RR be a holomorphy subring of KK, not equal to KK. We prove the following undecidability results for RR: If KK is recursive, then Hilbert's Tenth Problem is undecidable in RR. In general, there exist x1,...,xn∈Rx_1,...,x_n \in R such that there is no algorithm to tell whether a polynomial equation with coefficients in \Q(x_1,...,x_n) has solutions in RR.Comment: This version contains minor revisions and will appear in Annales de l Institut Fourie

    Degree spectra for transcendence in fields

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    We show that for both the unary relation of transcendence and the finitary relation of algebraic independence on a field, the degree spectra of these relations may consist of any single computably enumerable Turing degree, or of those c.e. degrees above an arbitrary fixed Δ20\Delta^0_2 degree. In other cases, these spectra may be characterized by the ability to enumerate an arbitrary Σ20\Sigma^0_2 set. This is the first proof that a computable field can fail to have a computable copy with a computable transcendence basis

    The King's many bodies: the self-deconstruction of law's hierarchy

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    The article connects two strands of the recent sociolegal debate: (1) the empirical discovery of new forms of spontaneous law in die Course of globalization, and (2) the emergence of deconstructive theories of law that undermine the law's hierarchy. The article puts forward the thesis that law's hierarchy has successfully resisted all old and new attempts at its deconstruction; it breaks, however, under the pressures of globalization that produced a global law without the state, as self-created law of global society that has no institutionalized support whatsoever in international poliucs and public international law. Consequently, the article criticizes deconstructive theories for their lack of autological analysis. These theories do not take into account the historical condicions of deconstruction. Accordingly, deconstructive analysis of law would have to look for new legal distinctions that are plausible under the new condicions of a doubly fragmented global society. The article sketches the contours of an emerging polycontextural law
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